Sometimes
by NomDuClavier
Summary: In which we learn the truth about what happened all those years ago in the lab, who Peter's mother is, who Peter is, what William Bell's role is in all of this, and much more - Peter/Liv, Walter/Astrid, Walter/?
1. Prologue

"**Sometimes"**

a Fringe fanfic in multiple installments

**Pairing:** Peter & Olivia (pre), Walter & Astrid (pre), ???  
**Genre:** Adventure/Romance  
**Rating**: T

**Summary: **In which we learn the truth about what happened all those years ago in the lab, who Peter's mother is, who Peter is, what William Bell's role is in all of this, and much more. This story will take the team all across the country in a bid to find the origin of The Pattern in order to put a stop to it.

* * *

Sometimes Walter counts out the Fibonacci sequence as he readies himself for sleep, the mantra helps him relax. Unlike Peter, who's decidedly less amused when yet another night his father recites – or sings, he does that too at times – yet another numeric sequence, or the so many digits of a fundamental irrational number. If he was aware he did it, he'd say it was one of his guilty pleasures, particularly the times he sings them in reverse order. He's certain he doesn't know he's doing it, it's not as if he goes out of his way to annoy his son; a scoff briefly interrupts the recital.

On more than one occasion Peter commented on this behavior, likening him to a deranged Count von Count – although he didn't use that specific word, what with St. Claire's and all, he's not _that_ callous – not in front of Walter, at least. The only thing the good doctor took away from this comment was a renewed interest in Sesame Street; that and it helps him relax, this reciting that he doesn't know he's doing. "Was I singing again, Peter?"

His wool-socked feet shuffle on the floor, were he someone else it might be considered embarrassment; it's actually a dance to the accompaniment of the Golden Ratio. Occasionally Peter wonders if he should be worried that he can tell what irrational number Walter's thinking about by looking at the man's feet.

Sometimes they allow Walter to slip into this transcendental and lucid state of mind, these calming choreographies of numbers and feet and wool, a mind unencumbered by years of neglect at the hands of psychiatrists he's certain found their degree in a box of cereal. On these rare occasions his mind tends to focus on what really matters to him, but finds frustratingly difficult to put into words any other time.

When he's finally relaxed to the point where he falls asleep, Walter often dreams of Peter, his wife, William Bell, the accident in the lab, The Pattern, his role in it all, only to forget about it in the morning. He'd curse the loss of his photographic memory, and is sure he's done so before, if only he could remember to. It's not that he's forgotten as much as misplaced the index cards, as if someone threw a tantrum in his head and pulled down all the filing cabinets, spilling his memories on the floor.

The mornings in the lab are all the same, except when they're different, and this morning is one of those. Walter's hand stills on Gene, cutting short the brushing as his face lights up, he turns to his lovely assistant – not really his, he knows, but ultimately doesn't care – with glee on his face and surprises her. "Astrid, I remembered something!"

Young agent Farnsworth ceases brushing Gene's teeth – no matter how often she says she's not going to brush the cow's teeth, in the end she knows she can't deny Walter. He really did it this time and she gives him a beaming smile. "Yes, my name!"

That so little a gesture as Walter's using her name can excite her so much is a bit unnerving, but she decides to go with the flow – it's the only strategy that works in this lab, she's come to realize.

Walter's face screws up. "No, no, no... I remembered something important!" As he sees her face fall, he quickly corrects himself and gives her what he hopes is a winning smile. "Not that your name isn't important, Astragal." He's seen Peter give that blonde woman a smile like that quite often – makes a mental note to give him that father/son talk - and hopes he's doing it correctly.

She can't help but smile knowing that at least once he got it correctly. "It's Astrid... what's important, Dr. Bishop?" _He's probably figured out what he wants for lunch._

"Yes, Astrid, I know your name; you're my assistant." He gives her a disapproving look for interrupting him – as if anyone couldn't remember their assistant's name, what a ludicrous idea. "No, I know what really happened, that day in the lab."

Walter nods to himself and continues brushing Gene, much to the cow's content. "Now, where were we... ah yes, lunch. Do we have any more of your boysenberry syrup?"

This must be one of those fleeting moments of lucidity Peter's warned her about. "I'll go and phone Peter now and ask, he can bring lunch." She takes a few paces to get out of earshot, calls Olivia. "It's Astrid. Bring Peter, Dr. Bishop has something huge to tell us. I only hope he still remembers when you get here."

-- == -- == --

Praise? Comments? Leave them after the beep.


	2. Get off my lawn

"**Sometimes"**

"**Chapter 1 – Get off my lawn"**

**Author's note: **I owe a massively dynamic debt of gratitude to my homie Lo for her efforts in proof reading this story. Any mistakes left are entirely my own. You're one of a kind, Lo.

* * *

When Peter and Olivia make it to the lab, throwing ever more unlikely theories at each other on what it is Walter might have remembered, the doctor himself is attending a Stanford lecture, or so he thinks.

"You fool!" Walter exclaims, apparently trying to address the professor giving the lecture, "A standard Boltzmann network doesn't have any such feature, its Hebbian nature prevents it. One doesn't use a stochastic recurrent neural network for a task like this, it's beyond believable."

That the professor in question doesn't respond to the accusation makes no difference to Dr. Bishop, who eagerly rants on. "Ask Geoffrey Hinton if you must, at least _he_ knows what he's talking about; _in my day_, guest lecturers actually _knew_ what they were talking about. The state of education is simply appalling these days," he turns to Astrid who's watching the scene with undisguised amusement, she being the one who had looked up the Youtube recording of the lecture earlier at the man's behest. "Don't you think so, dear? You turned out remarkably well, considering."

Not knowing what to do except confirm his statement she does so, then looks helplessly towards Peter. "Yes, Dr. Bishop, I agree. Thank you for the compliment," she adds a near silently muttered, "backhanded as it was."

Olivia leans in towards Peter even more than she has been, meaning that now she practically rests her head on his left shoulder, and whispers, _"You know what he was talking about?"_

Deciding to tackle the bull horns first, Peter takes the question back to the source, translating to less jargon-filled English on Olivia's behalf. "I see you disagree with Stanford's approach to teaching artificial intelligence and machine learning, Walter?"

"Nincompoops, why anyone would pay tuition to learn something I worked on back when I was your age, I cannot imagine, and if only they were taught correctly. This sad excuse for a professor won't even acknowledge the problems I have with his teaching methods, he just proceeds with his pitiful lecture as if he didn't hear me..."

Walter pauses and thinks for a moment, the equipment must be at fault, it's not as if someone would dare ignore him. "How _can_ the FBI get any field work done when teleconference equipment fails this spectacularly, I find myself wondering now. Agent Dunham," Walter brings his impressive focus to bear on the woman in question, "can you see this gets fixed, I can't get any work done with hand-me-down tools like these."

"Walter," Peter walks over to his father and puts a hand on his shoulder to try and calm him down, "it's a _recording_. You can yell at them all you want, they won't hear you. There's nothing wrong with the teleconference equipment, this is just one of the lectures you can find on the Internet."

Walter, upon learning a new concept, is instantly interested, the brunt of his irritation vanishes like snow before the sun. "Internet, you say ... What is this Internet of which you speak, and what does it do? And how does that excuse them from inviting brain dead guest lecturers?"

Astrid shakes her head – she's tried to explain the Internet to Walter before. _Please don't say it's a series of tubes or that Al Gore invented it._

She hopes that Peter somehow picks up on her thought, then walks over to Olivia, whispering to her, _"If you get a chance, ask him about what really happened at the lab, that's what he said he remembered. I'm out getting some fresh air, I need it, be back in 15."_

She walks out, shaking her curls some more as she continues muttering to herself. "I'd fit in at my new job, _right _... Baldy's likely never had the pleasure of working a full schedule with Walter, it's like babysitting Catweasel's genius brother sometimes."

The fact that unlike most times when Astrid's thoughts turn to Dr. Bishop, this time she addressed the irascible man by his first name, is something that's lost to her. She pushes open the doors and cool winter air greets her with welcome relief.

-=-=-=-

Sometimes Peter can strangle his father, such as times like these when Walter picks up on the undercurrent of his affection towards Liv, then proceeding to quiz them about it in detail. This particular morning, being given to belief earlier that Walter has something important to share, only for him to be found ranting at a recorded lecture, is high on the list of all time favorites, if you could call it that.

As soon as Astrid has vacated the premises, Olivia makes an attempt to ask Walter what actually did happen "at the lab", hoping he meant the incident that sent him to St. Claire's all those many years ago. She suspects that whatever or whoever is behind The Pattern, it is rooted somewhere in the past, and uprooting Walter's past may just be the thing to provide them the first tangible lead in ... ever since she started working the cases. "Doctor Bishop, can I ask you something?"

"Call me Walter, you're practically family." Walter gave a meaningful glance to his son. "Peter speaks very highly of you."

She tries to hide the surprised look on her face she knows is forming there, then looks at Peter who shrugs – he had after all remarked to Walter about a certain efficiency she possesses, but is nonetheless surprised himself to have Walter include her in their dysfunctional little family. It just means he has to get those now suddenly inappropriate feelings for her under control – when it comes to Walter, the best strategy appears to be to simply agree. "Walter, I've been meaning to ask ..." Liv restarts.

"How long my son has been fond of you? I don't know exactly ..." He sinks in thought for a moment, completely oblivious to the sudden outcry of "Walter!" from said son. "Oh yes! I believe he called out your name a few times in his sleep last night. Actually, come to think of it, he was a bit loud."

Peter tries once more to stave off the inevitable embarrassment. "Walter!"

"Walter, I don't think that's ..." Olivia tries, getting nowhere fast.

"I'm multi-orgasmic, you know, or at least I think I am," Walter pipes up once more. "Tell me, does Peter have this trait as well, Agent Dunham? Can I call you Olivia, you are dating my son after all, are you not?"

"Walter! That is _not_ a topic available for discussion like this, understand?" Peter is seriously starting to lose his composure, Walter really is utterly incorrigible; he wonders briefly if the mother he hardly remembers instilled his sense of propriety, it evidently didn't come from Walter. "For the last time, Olivia and I are _not – _and I repeat:_ not!_ – dating, and because satisfying your curiosity appears to be the speediest way to make this line of questioning go away: neither did we engage in intercourse, nor have we kissed. Stop making up things that aren't _there_. Satisfied now?"

Olivia doesn't exactly know what to do. Is the correct response to this to blink and say nothing, open and close your mouth like a goldfish on dry land, what exactly does one do after a revelation of this kind?

Peter can deny it all he wants to his father's face, the way he did it speaks volumes to her; it is undeniable his mouth had said one thing, when it would much rather have been kissing hers hard instead, leaving her lips swollen in that way she likes, biting her lower lip for a moment as he pulls back to look into her eyes.

That at least is what her FBI-trained observation skills are telling her; she hadn't just been fantasizing about him, honestly. Peter – the people person between the two of them – was really the person to ask and read someone's intentions; asking him to read his own would be a bit convoluted, beating around the bush. She supposes she can just outright ask him if he wants her _like that_, but won't that upset the balance of their working partnership and invite disaster?

"I think I've broken your girlfriend's brain," Walter remarks, seeing Olivia gaze off into nothingness and blinking every so often, "we need to get her back in the tank."

"No Walter, whatever else, no more sessions in that tank. And her brain isn't broken – beyond giving her Scott's memories, that is – I think you shocked her, sharing your theories about us like that."

"Hah!" Walter exclaims triumphantly, "So you _don't_ deny she is your girlfriend!"

Peter's at wits end and throws his hands up into the air, calling to any deity that will listen to come down and talk some sense into his father, a testament to his annoyance with the situation that he does this, not having prayed in ... he can't recall the last time; in fact he draws a blank on mostly any experience at all before his thirteenth birthday – exactly, to the day. Rather than get into that now, he files away this information, determined to get to the bottom of it.

_Add yet another mystery to this motley crew's case load; all we need now is a van and a dog, and we can get ourselves a TV show._

Liv blinks and shakes the cobwebs from her mind.

"Peter and I aren't dating, Walter." She manages to get out, having somewhat recovered from Walter's confession. It wasn't something she wants to imagine.

_If it were Peter who'd mastered Tantric sex, wait ..._ She catches herself, dangerously close to letting her FBI skills run away with her again.

"And the two of you haven't even kissed, so you say. What a waste of perfectly good unresolved sexual tension ..." The doctor trails off, thinking hard already on how one would capture this thing he decides to call UST, yes that's as good a name as anything, and how to distill it down into a liquid that might serve the basis for an exclusive perfume line, bottle it, sell it, make quite a mint. He nods to himself. "It would be quite the hit, come Valentines Day, indeed. Maybe mix it with some boysenberry essence. Call Asparagus, will you? We need to get on this right this minute. The two of you can start kissing – I'll observe and try to find a way to harness the resulting energy."

The younger of the two Bishops looks to his blond partner, feigning a nonchalance he tends to master but which is totally lost to him this minute. "You know, if we give him what he wants, maybe he'll leave us alone for the rest of the day and we can actually get around to asking him that question we came in for."

"Right, the two of us alone, very good idea," Liv agrees. Uncountable heartbeats pass before she adds an afterthought, "you know, so we can find out exactly what Astrid called us in for."

Their mouths meet and their overactive minds come to an abrupt halt, the deceleration of which sends them flying with a force neither had expected. When two minutes later they come back up for air, Peter nips at her lip before he pulls away to look into her eyes, seeing the same stunned expression there he's sure he must wear himself. "Ho-_ly_ crap!"

"Yes!" Walter finds it hard to keep still, unbridled with enthusiasm as he is, "I'll figure out how to sequester that energy, it certainly looked like it was off the charts, and if a kiss is like that, just think of when the two of you ..."

"NO! Walter, just _No!_ Do _not_ finish that sentence. _When_ and _if _Olivia and I decide to go there, you will be somewhere else entirely, are we _clear_?"

Walter is now extremely pleased with himself. There's no such thing as a method to capture and distill sexual tension – he should know. An entire year of research was wasted when he first discovered the concept as a teenager, he'd just tricked his son into doing something the young man wanted to do already, perhaps now with some of that UST resolved the atmosphere would start to lose some of its tension. "Now about those boysenberry pancakes I wanted?"

-=-=-=-

Astrid wasn't entirely certain if she should believe her eyes.

The simplest explanation for what she is looking at has to be that the "Pattern" has thrown her into the future, and that Liv and Peter were engaging in a holiday tradition. Of course there's always the possibility Walter has spiked their drinks with love potion number 5.

Walter had made an off-hand remark once how it wasn't number 9 – he should know. After all, he'd been the one who had produced the world's first viable love potion – where viable means scientifically proven to work, he'd been very clear on this point – and it had taken _5_ batches to get it right, not _9_. What did she take him for, an incompetent imbecile? As his assistant, she should know better by now.

Disregarding her mind's excursion to Walter, she again focuses on what she is looking at: two people with unflappable exteriors she thinks she knows well, yet they're flapping their lips against each other's in a way that makes her think she doesn't know them that well at all. There had been no indication that this was about to happen when she went out for a breather ... it just didn't happen, except that it was happening, right before her eyes.

"Ho-_ly_ crap!" She echoes the sentiment, then quickly walks back out collecting her wits for a moment. One thing she was certain about, Liv and Peter likely did not want her to see what was happening.

A few minutes later, after composing herself and giving Liv and Peter time to come up for air, she reenters the lab, ready to make some pancakes.

_Making pancakes isn't a euphemism, get a hold of yourself, Astrid. Next thing you'll find yourself wanting Walter to flip you over and start dribbling boysenberry sauce ..._

Not that anguished noises are that unusual, taken in context with Walter Bishop's lab, when that outcry of anguish emerges from Astrid Farnsworth, it does tend to get noticed.

"Is everything quite alright, Asunder, dear?" Walter offers with a friendly smile, sending Astrid for an ever greater loop.

"No, no, no ... I mean, Yes! Everything is alright, quite alright in fact. I was just ..." She thinks quickly to cover up the direction her thoughts had taken her, sure as she is the make out session she'd witnessed earlier is all there is to it. "Thinking back to last night's episode of The Office. Can you believe Phyllis would _do_ something like that?"

"Quite ... well, if you're certain you're alright. Maybe you'd like us to make some pancakes? I'd like mine with the bottle on the side; you know how I like to dribble with my syrup." Walter gives her another brief smile before returning to Peter and his girlfriend.

_Why, oh why must the man always say the most inappropriate thing possible. If it's not "I just got an erection", it's a double entendre._ Astrid sends her curls flying again with another shake of her head, then busies herself with lunch in the hope it will distract her.

"Oh, did you know?" Walter is suddenly at the stove with her, his breath caressing her neck as he stands just off to the side, his upper body angled toward her as he speaks. "Peter and his girlfriend kissed earlier. It's a shame you missed it."

The doctor wonders momentarily if the sudden blush creeping up his assistant's neck is a belated reaction to coming in from the cold, an experiment ought to provide an answer to that. _A sweat lodge, frozen lake, log cabin, rum raisin ice cream, Areola herself, of course ... oh, and some of that boysenberry syrup that makes me wonder if her purple lip gloss alters its taste; good, another experiment, right there._

"They ... _kissed_?" Astrid tries hard to feign ignorance.

"Oh, yes. It was quite riveting to watch because they were "riveted" together, so to speak." He's quite pleased with his little simile and makes no attempt to hide the fact – Walter Bishop has never been known for false modesty.

"But ... how?" Astrid asks, still not understanding the mechanics that brought the two together in the first place.

She was certain Olivia would have held off the boat, what with the mistake of Titanic proportions her liaison with John Scott had been. _You'd think that Liv would take the FBI fraternization guidelines to heart after last time, evidently complicated is a turn on for her._

"How?" Walter's brow furrows in thought a second, then Astrid finds herself in a lip lock reminiscent of the one she'd walked in on before. "Like that, I suppose. Although perhaps Peter is better suited to demonstrate, assuming of course Olivia wouldn't be adverse to the idea. I have no knowledge of how monogamous they are, you see?"

Had Astrid had the capacity for speech at the moment, she would have said something along the lines of _"I meant why!"_ or "_Who do you think you are, kissing me like _that_, then walking away!"_ Sadly these thoughts didn't occur to her until the aroma of scorched pancakes filled her sinuses.

_Walter, Walter, Walter, Walter._

-=-=-=-

"Have you seen Astrid, Walter?" Peter asks, "She should've been back by now."

"Yes, I just kissed her in the kitchen – she's making pancakes." Walter confirms.

"Wait. Is kissing another synonym for running into I wasn't aware of?" Olivia inquires.

Peter scoffs. "If you mean slowly running into, with precision, then yes ... it's a synonym. What _were_ you thinking, Walter? First you stab her with a syringe, now you kiss her?! Do you _want_ her to quit?"

Walter is genuinely perplexed – what on Earth would give Peter that idea? "Not at all, she's my best assistant ever. At least, I think so – I don't exactly recall all of the previous ones ..."

Before Peter finds himself a chance to respond, Walter's jaw sets and his eyes burn with anger. "How_ dare _you imply I'm such a horrible kisser that Astrid would quit over it, that ... that's just so uncouth I can't find the words to express how much ... there are just no words. My own son doubting my ability to kiss, exactly how did you think I won over your mother?"

"I apologize for questioning your ability to kiss, Walter." The son lets out an exasperated sigh.

Peter, like his father, sometimes finds it impossible to let a subject go; this time he is certain the situation merits it. "Let's try this again, shall we? Astrid – Why. Did. You. _Kiss._ Her?"

"Oh, I told her the two of you were making out like teenagers earlier, and she asked how." That to Walter this makes all the sense in the world is evident, he relayed this in much the same manner he would use quoting the current drawn by a coffee maker; it's just the way it is, questioning it unless you intend to design something better is a waste of energy.

'_It must be a Thursday, I never could get the hang of Thursdays,'_ he quotes Arthur Dent to himself, feeling just as lost as the guy who woke up to see bulldozers about to flatten his house to make way for a bypass.

Peter takes a deep breath, leaving the conversational ball in Walter's court isn't going to get them anywhere, and he decides to take charge – thinking as an aside that his asserting himself might even be a bonus point in Liv's book. "Right then ... Liv, you check that Astrid hasn't been rushed to the hospital in a state of shock, and I'll find out what it is exactly we were called in here for this morning."

Walter's face brightens again, Peter's cue jogging his memory once more. "Yes, yes. What really did happen in the lab all those years ago – I remembered it this morning when I woke up."

These periods of lucidity of Walter's being as unpredictable as the man himself, Peter decides to press the issue. For all he knows, seconds from now the memory's buried again in the avalanche of information Walter calls a brain.

"Want to tell me about it, dad?" He feels guilty using the familial when he's still making the reconnection, for now there is nothing for it, he'll let his moral code chastise him another time.

"It was your mother, son. Some 17 years ago, when the lab exploded and killing the assistant with it ... I think it was she that caused the explosion."

Peter has no words – for once he draws a complete blank.

Walter continues, oblivious to his son's reaction or lack thereof. "I'm certain it was her, although I didn't make the connection until just now, you see. She looked a bit different from when we were married together, as if she'd altered her appearance after she left us."

"Mom?" Peter's voice takes on the timbre it had when he was a little boy, when he still had this mysterious mother. He slides down the wall, hard, sitting on the cold floor.

Walter is lost in his own thoughts and doesn't see his son's losing it. "Oh yes, no doubt about it; it's the eyes, you see. I never forget a pair of eyes."

All Peter's eyes see are his eyelids shutting the world out before he succumbs to darkness.

* * *

**A/N: **With apologies to the Stanford faculty; they're really informative lectures, Walter just happens to disagree.

Random Fringe Prediction: Peter and Olivia will have their first on-screen kiss in the season 1 finale.


End file.
